Smart energy (“SE”) devices and networks have been deployed in homes and businesses as utilities and consumers attempt to better understand and control energy use. SE networks are typically a collection of monitoring, control, and reporting devices located, for example, in a home. Typical SE devices include, for example, thermostats and water, gas, and electric meters. The SE devices generally implement one or more communications protocols to communicate with each other and ultimately the utility or consumer.
Network devices, such as those on the SE network, may attempt to communicate with devices on a different, or external, network. The external network may be different than the SE network, such as implementing a different communications protocol or addressing scheme. To facilitate these communications, a gateway may be used to interface between the SE network and the external network. The gateway may be a node on the SE network and may include the appropriate hardware and software to connect to both the SE network and the external network, as well as the appropriate hardware and software to route communications between the two networks.
The SE devices on a SE network may be interconnected in various ways but are often connected, at least in part, wirelessly. The SE devices may communicate data using radio frequency (“RF”) signals. One way the SE devices may be organized is as a mesh network. A mesh network may allow one node to communicate with another node using multiple hops through peer nodes on the network instead of transmitting data exclusively through a dedicated network infrastructure device, such as a switch, which may then forward the data directly to the recipient node. Mesh network nodes may be able to dynamically reconfigure communication paths around blocked or malfunctioning nodes. A wireless mesh network may be a wireless ad hoc mesh network, meaning that it is self-configuring. As such, the network topology of the ad hoc mesh network may change rapidly.
The wireless mesh network may be a wireless personal area network (“WPAN”). WPANs tend to be used for general purpose, inexpensive, mesh networks such as, for example, industrial control or home automation. An example of a WPAN is a ZigBee wireless network. A ZigBee wireless network implements the IEEE 802.15.4 communication protocol standard for WPANs. WPAN node devices are typically low power [e.g., 1 milliwatt (mW) to 250 mW] and have lower data rates [e.g., 250 kilobits per second (kbps)] than node devices for other networks.
WPAN node devices are typically powered by either an external power brick requiring a power cord or are powered by batteries. WPAN node devices having an external power brick are bulky and may make a WPAN less convenient to implement. Such WPAN node devices often require additional mounting hardware or a special installation which can be expensive and cumbersome.
A WPAN implemented using battery powered node devices tries to conserve power and extend the life of the batteries of the individual nodes. To extend the battery life of battery-powered nodes in WPAN applications, the nodes may be required to enter a very low power mode for most of the time that the network is operating, which results in decreased throughput. Periods of high network traffic can quickly drain batteries. Furthermore, when batteries reach the end of their life, battery powered nodes require more maintenance and pose a higher risk of network failure.